Understanding the Turn Four Rule

The January 18 banlist announcement is now a month and a day away. If you play Modern, there’s an excellent chance the inquisitors of the Modern community will scrutinize at least one of your decks. Probably all of them. Since December 1 alone, I’ve seen serious ban discussion aimed at Burn, URx Twin, BGx Midrange, Affinity, Tron, and Amulet Bloom. As in, all of Modern’s current Tier 1 decks. Ban mania has never been more real. Steve Horton wrote a great article for GatheringMagic the other day, summarizing Modern banlist opinions of seven different high-level players. Their consensus? Only that there is virtually zero consensus on what needs to be banned and unbanned in Modern. Such diversified banlist stances rarely arise from metagame statistics or Wizards’ past decisions, instead drawing on hyperbole, personal anecdote, and theorycrafting. And in all that discussion, it seems there is no aspect of the Modern banlist more misunderstood and misrepresented than the “turn four rule”.

In its most basic form, the turn four rule gives Wizards the opportunity to ban cards that win too fast in Modern. In practice, the rule and its application are much more muddled. Today, I’ll try breaking down the turn four rule and its history in past banlist updates. I’ve touched on the rule before, including in my first banlist prediction on the site, my retrospectives on the 7/18 and 9/28 announcements, and a Q&A-style article during July. In today’s piece, however, I’ll be focusing exclusively on the turn four criterion, unpacking its definition through metagame analysis and Wizards’ language in past updates. Although only R&D knows the exact parameters around the rule (if they can even be described as “exact”!), we can use public information to get the best possible working definition behind the turn four guideline and how this rule could affect future updates.

Turn Four Rule Basic Definitions

If you’re a Modern superfan like me, you probably have the turn four rule memorized. Well, maybe not: this says a little bit more about my priorities than it does about the rule’s value. Even so, given its relevance in banlist updates, it’s hard to understate the rule’s importance. Writers and players certainly mention to it all the time. Unfortunately, they often miss key parts in its wording, referencing general premise but not specific language. In this section, we’re going to get on the same page about the rule’s exact wording and see where the inconsistencies arise.

…the DCI’s stated guideline for the Modern format [is] to avoid… having top-tier decks that consistently win on turn three (or earlier).

There’s significant overlap in Lauer’s two definitions. “Top-tier decks” and “turn three (or earlier)” show up word-for-word in both announcements. 2011’s “consistently” morphs into 2013’s “frequently”, but the underlying meaning remains the same even if the specific adverb doesn’t. Together, these two quotes form the canonical turn four rule as we know it.

Or, should I say, as we don’t know it. For most Modern authors and players, the turn four rule starts and stops at decks “win[ning] on turn three (or earlier)” clause. They typically ignore the deck’s tiering. Are these commentators just ignoring Lauer’s statements? Or is something else causing them to misrepresent the rule?

Clearing Up Misconceptions

If you’ve read past Modern announcements as much as I have, you probably noticed I pasted only an excerpt of Lauer’s September 2011 quote to highlight certain language. Here’s the paragraph in its entirety, which points squarely at where the turn four rule misconceptions originate (emphasis added):

Before Pro Tour Philadelphia, the DCI’s stated guideline for the Modern format was to avoid having decks that consistently win the game on turn three. With the results of the Pro Tour in, we are tweaking that goal to not having top-tier decks that consistently win on turn three (or earlier). We also have the goal of maintaining a diverse format.

It’s all starting to come together. The bolded piece refers to the initial phrasing of the turn four rule, which shared the “consistently” and “turn three” elements but made no reference to the “top-tier” qualifier. As Lauer explains, the DCI updated this older rule following Philadelphia, inserting the deck’s top-tier status alongside the consistency and speed dimensions. Writing just a month before Lauer’s September announcement, Tom LaPille articulated this first definition at the rule in the seminal “Welcome to the Modern World” article while discussing the preemptive banning of cards like Dread Return (emphasis added):

…we have a rule of thumb about Legacy that we don’t like consistent turn-two combination decks, but that turn-three combination decks are okay. We modified that rule for Modern by adding a turn to each side: we are going to allow turn-four combination decks, but not decks that consistently win the game on turn three

This bolded section shows us both the birth of the turn four rule, and also where most Moderners get led astray. If you don’t read the later releases by Lauer, you have no way of knowing that the oft-cited, seldom-quoted rule eventually came to add the “top-tier” criterion. Given the buzz around Modern’s launching article, and the relative drone around adding a qualification to the turn four rule, it’s no wonder people forget the updated phrasing.

Going ahead, we need to revise our understanding of this banlist rule to fit its 2011 and 2013 language. After today, I hope all of our readers keep the newer definition in mind, which I’ll repeat here to drive the point home:

The DCI’s other primary goal for Modern is to not have top tier decks that frequently win on turn three (or earlier).

Three Pieces, One Rule

Now that we have the ruled laid out, we need to isolate its three dimensions and see how each contribute to the rule as a whole. Given both the rule’s wording and Wizards’ execution of that rule, all three of the rule’s criteria must be met for a deck or card to be in violation. If we are to apply the rule, we need to understand each of those components. I’m going to go over these factors in reverse order, starting with the most obvious and ending with the least (which, incidentally, is also the least-remembered). One last note before we start: remember we are only inferring R&D policy from past decisions and actions. It’s entirely possible their actual process is different from the one we are reviewing here. Even so, we have a much better chance of understanding the process of we stay in conversation with the evidence and historical precedents.

1. The violating deck must be winning “on turn three (or earlier)“

Given the name of the rule itself, this qualification doesn’t need much repeating. If a deck is winning at all before turn four, it has already tripped the first step of the turn four rule. Of course, if you’ve ever browsed Gatherer for the next broken combo, it takes about two minutes to find some fragile interaction that ends the game in the turns 1-3 range. Who doesn’t want to lead a mana dork into turn two Wall of Blood into turn three Rite of Consumption? That doesn’t even count the mainstream ways to close a game by turn three, whether in Infect, Amulet Bloom, Affinity, or even Twin decks powered by Simian Spirit Guide.

Given the sheer range of cards that can theoretically win on turn two (we could make a drinking game around ways to take games off Tainted Strike), cards have never been banned for just being part of a hypothetical fast win. As LaPille wrote in his August article, the turn three cutoff originates in Legacy’s turn two cutoff, and we know Legacy has even more theoretical turn one wins than Modern. Neither format has a banlist with hundreds of cards, so it’s clear there’s more at work in this rule than just winning on an early turn.

2. The violating deck must be achieving these wins “consistently/frequently“

Phew. I guess all those Tainted Strike decks are safe after all! Once a deck has been identified as winning before turn four, Wizards also looks to see if the deck is doing so consistently. This is the first area where the turn four rule takes a dive from objective, measurable clarity (the hard numbers of “turn three or earlier”), to subjective, open-ended rhetoric. What exactly qualifies as consistent? Winning too fast in 10% of games? 25%? 33%? And how does Wizards even calculate consistency in deciding on bans?

Let’s start with the calculation question. It’s critical to understand Wizards’ measures of consistency are not derived from solitaire, goldfish games. Win-turn frequency comes out of real games against actual opponents. We have two pieces of evidence for this. First, in the January 2013 update, Lauer states why Storm was targeted for banning: “Looking at the results of games, turn-three wins are frequent for Storm…” The “results of games” reference clearly suggests actual games with measurable results, likely on MTGO where such data would be easily amassed. Second, and far more explicitly, Aaron Forsythe tweeted this statement right after Song got axed:

@surgingchaos Golfishing a turn-three win is not the same as actually winning a significant percentage of real games on turn 3.

These pieces of evidence overwhelmingly point to Wizards using win-turn percentages in actual games, not goldfish simulations, to determine a deck’s consistency.

This still doesn’t answer questions about the numeric cutoff itself. Is there a turn 1-3 win percentage that, if exceeded, leads to immediate ban scrutiny? If so, what is the breaking point? Unfortunately, Wizards doesn’t release these numbers, probably for similar reasons to why they stopped publishing all the MTGO Daily results years ago: it leads to easily solved formats. It also leads to extensive backseat driving by a community that might already be too vocal. That said, it might be possible to approximate this cutoff by assessing the percentage of games where pre-2013 Storm won on turn three or earlier.

We can make a rough estimate using feature match narratives from all events where this deck saw play. We’ll use both Epic and Ascension Storm numbers for our math: as Storm pilots Matthias Hunt and Kyle Stoll explained, Epic Storm is faster than the Ascension version. This lets’s us leverage both Ascension and Epic Storm numbers to get at least a floor for the win-rate. Including events between Pro Tour Return to Ravnica and Grand Prix Lyon, we have eight feature matches spanning 18 games. Storm won four of the eight matches (50% MWP) and eight of the 18 games (44% GWP). The deck won four of its eight games on turn three. Stated differently, 22% of Storm’s total games ended with a Storm win on turn three. Conducting 10,000 resamples to account for our initial low N of 18, and then using the Mean Squared Error to get indicate the accuracy of our estimate, we find Storm has a turn three or earlier win percentage somewhere between 17% and 30%. Variants using Epic Experiment were likely even higher.

If your deck is winning on turn three or earlier in that range, you might want to be careful. Especially if it’s in the upper end of that range from 24% to 30%. Naturally, this is only an estimate based on the data we have, so it suffers from numerous limitations. That said, it’s the best stab at quantifying consistency I have seen, which suggests we should stick with it until we get more information.

When the January 2016 announcement comes and goes, we’ll be able to asses the win percentages of current decks (such as Amulet Bloom and Become Immense Infect) against their ultimate banning fates. If one were to survive and the other were to perish, we might be able to further triangulate a cutoff. For now, we’ll keep the “consistency/frequency” measure around our 24% calculation.

3. The violating deck must be “top-tier“

We end with the turn four qualifier that got left behind, the 2011 and 2013 addition most players forget when are arguing bans. It’s not enough for a deck to be winning before turn four alone, even if it’s doing so consistently in real games. That deck must also meet Wizards’ definition of a top-tier strategy to fall in banning crosshairs. Although Wizards never explained why the DCI added this clause, there are at least two possible reasons we can infer.

The first likely explanation is statistical. Unless a deck is top-tier, Wizards is unlikely to have sufficient matchup data to calculate a meaningful turn 1-3 win-rate. Stated simply, N is just too small. If I’m taking names with my sick Soulflayer blitz deck in the MTGO practice rooms, I might only be contributing 10-20 matches per week to the Wizards dataset. That’s not nearly enough information for Wizards to calculate my turn 1-3 win-rate, especially against major decks. Maybe I’m regularly facing non-interactive Nykthos Green players. Maybe I’m running hot. Maybe I’m queuing up at a time of day where my opponents are exhausted and playing poorly. Wizards can eliminate these explanations with enough data, but if the deck isn’t top-tier, it won’t contribute enough data to reliably determine the win-turn rate.

The second possible reason is metagame oriented. If you go to a tournament, you expect to have some number of interactive games of Magic, and some smaller number of less interactive games. When Modern has too many top-tier decks winning too quickly, player enjoyment drops, event attendance suffers, and Wizards and its tournament organizers lose money. It’s also bad for long term format health and community buy-in. Low-tier decks don’t cause these problems because few people are running them. Did Puresteel Paladin Cheeri0s combo you out for the first time in your career? You’ll probably laugh at this amusing novelty. Did Epic Storm run you over for the fourth time on a Grand Prix Day 1? You’ll probably lose your flippin’ mind. This balance is likely another factor at play in the rule’s top-tier qualifier.

This raises a similar question to one we saw in the consistency section: how does Wizards actually define “top-tier”, especially with respect to the turn four rule? Again, history gives us a few examples of this in both the Seething Song ban and, one we haven’t examined today, the Blazing Shoal ban. Here are some metagame statistics for Storm at the time of its banning:

If you were to speak in terms of the Nexus’ tiering, these figures suggest Wizards is willing to consider decks to be “top-tier” if they meet either our Tier 1 definitions or the high-end of our Tier 2 parameters. This is a fairly wide range and is something to be mindful of. If you think a deck is top-tier, compare its metagame shares to these kinds of numbers. Rule for the wise: if the deck in question is Tier 1 or at the upper-ends of Tier 2, it could potentially be considered “top-tier” by Wizards. This is certainly not to say Wizards uses our tiering in making decisions (if only!). Rather, we can use our numbers as indicators of the Wizards thought process.

Applying the Turn Four Rule

Bringing things to a close, here’s the turn four rule one last time with some of our estimated numbers thrown in for additional accuracy:

The DCI’s other primary goal for Modern is to not have Tier 1 or high-end Tier 2 decks that win on turn three (or earlier) in 24%-30% (or higher!) of games.

This isn’t the only way to understand the rule, but it is probably the most precise and the one most in dialogue with the rule’s history.

(Author’s edit: clarified the range to include numbers that are even higher)

Hopefully this article helps us reach a sharper understanding of the turn four rule, its background, and its specific clauses. Use these definitions to access ban statements you stumble upon during your Modern travels. For example, all the talk about a Goryo’s Vengeance or Nourishing Shoal ban collapses once we consider the top-tier element of the rule. With a metagame share under 1% and no major wins since Grand Prix Charlotte and a lone Premier IQ victory, Grishoalbrand isn’t remotely top-tier and is extremely likely to evade the rule’s application. As a final thought, this article also leaves open the question of what card should get banned once a deck is identified as a violator. Sounds like a great topic for another day!

What are some other important turn four rule pieces you think need to be discussed? How else can you apply the rule? Do you have any overall thoughts on Wizards’ definitions, or their pursuit of the rule in practice? I’ll talk to you all in the comments and look forward to next week when we add more exciting banlist discussion to the ongoing dialogue.

Sheridan is the former Editor in Chief of Modern Nexus and a current Staff Author. He comes from a background in social science data analysis, database administration, and academia. He has been playing Magic since 1998 and Modern since 2011.

21 thoughts on “Understanding the Turn Four Rule”

Is top-tier? Showing ~5% on your metagame share chart – easily around the levels of infect-shoal and storm

Can do it consistently?

Oh… hrm… Sheridan could you please do some kind of study of this? ;p I have no idea what data would be accessible to see if it clocks in in the 20-25% range for t2/t3 kills but its gotta be close.

How would you account for “virtual t2/3 wins” off of early titans? Hive mind is the only way you literally kill a 20 life opponent that early – otherwise your titan is connecting for 16 max in its first hit (stronghold + fortress). But more commonly the titan hits for 8 on turn 2/3 and you’re just virtually dead since if you had had the answer to the titan you presumably would have used it then, so the subsequent hit for 16 (and/or the parade of additional titans) is just going through the motions.

It seems entirely plausible that against most tier-one manabases that are trying to disrupt Amulet as soon as possible, 16 damage from Titan/Stronghold/Fortress would do the trick on turn 2 or 3. That’s two fetches and a shock. Turn one Polluted Delta fetching Steam Vents, turn two Bloodstained Mire fetching Swamp seems perfectly normal in Modern.

You CAN’T connect for 16 in T2 without multiples amulets. On T3 you can, but by then you should have an answer.

In the same way, a burn deck with a good hand (analogue to a Amulet Bloom hand that can summon a T2 Titan) WILL kill you in T3 if you do nothing besides shocking yourself by turn 3, same way a Titan will. It will even roughly do 8 damage with 3 cards on T2, the same way a Amulet Bloom does.

So it is not the Amulets fault for being too overpower that killed you in T3, it’s yours for failing to interact properly. The Titan portion of the deck is hardly what offends the Turn 4 rule.

I can see and would agree with the discussion if the “Ban Train” was focusing on Hive Mind and Hive Mind ALONE. But no, people focus on Amulet of Vigor and Summer Bloom, wich are not the cards to ban.

Banning them would only kill the deck, when you could in fact only ban Hive Mind and still have a just semi-decent midrange deck with some combo-portion attached to it in the same vibe as Abzan Company have.

Well, it still means that a turn 2 titan will kill you on turn 3 if you don’t have the answer – and to be fair there aren’t that many answers to the card that come down that early to interact. We’re pretty much talking Path to Exile, double-bolt, and Terminate if the titan resolves, and Thoughtseize if you’re getting it before it resolves. Mana leak might work if you’re on the play but is otherwise a pretty embarassing answer to a big mana deck like bloom.

Assuming the deck needs a nerf (depends on actual win rate pre turn-4) there is certainly a secondary question of whether its summer bloom, amulet of vigor, or hive mind that should go. Hive Mind gets rid of the turn 2 kill perhaps, but the turn 3 kill is still alive and well and if its still doing that 25% of the time then its still too strong and we will have gone after the wrong card.

The deck disappears completely if you take amulet. It might stick around with a summer bloom ban since Azusa can play a similar role while coming down a turn later and being vulnerable to lightning bolt.

I’m going to try a similar method used in estimating the Storm win-turn rates to see if we can find one for Bloom. I also have a large MTGO dataset I’m going to try and pick through. My guess is that Bloom is in the 20%-25% range, although I’ve seen some players that put it as low as 10%, and some sources (Tom Martell speaking off the cuff) putting it at around 30%. So it’s an open question, but one I hope to address with some more data analysis!

As for virtual wins, I have no idea how I’d account for them. So far, the turn four rule hasn’t actually mentioned “virtual wins”. This concept really only arose, at least through official channels, in that Stoddard Modern Development article from the spring, and even then it wasn’t an explicit reference to past bans. It’s murky territory overall, so I’m just leaving it on the side for now.

When I play Amulet, I never win 25% of my games on turn 3 or sooner. I played it at a local Modern event today, and in the 9 games I ended two games before turn 4. However, one was a turn 3 attack for 20 in which my opponent conceded on his turn, and would have been a turn 4 lethal attack since he blocked on turn 3 and didn’t die. The other was a game in which I only attacked for 8 on turn 2, and my opponent conceded before the game ended. I’d actually say that you have hands that don’t really do anything more than you have hands that make 6 mana before turn 4.

The thing to remember with Storm is that you legitimately end the game on turn 2 or 3, whereas Amulet often puts the game to “you’re most likely to win” rather than completely over. There are usually ways to interact with Amulet in those situations. It would be really interesting to see if Wizards counted those games or not.

First off you cant account for “Virtual turn 2-3 wins” because they arent wins. you are failing to take into account all the 1 and 2 mana removal. Any talk of “virtual” wins should be null. Second you should understand what the deck is capable of before you discuss its ban. The deck wins on turn 1, 2, and 3 almost as easily with titans as it does with hive mind.

Regarding the consistency/frequency clause of the Turn 4 rule, I have always felt that the standard shifts along with the turn of the offending “pre-4” win. For instance, if WOTC feels that winning 33% of the time or more on Turn 3 is the cutoff, is it also 33% of the time on turn 2? Or is there a smaller threshold for Turn 2 wins? Perhaps 16.5% of the time? Of course those numbers are used entirely for the purposes of the question and are not based on any particular deck. But the point is that it seems there is and should be a lower tolerance as the win happens earlier. In other words, the definition of “consistent” changes based on the turn of the kill.

That’s definitely possible. I do know that Storm very, very rarely won on turn two (you’d need a really crazy hand and lucky draws to do that), so this is mostly something for older bans like Shoal. The best way to figure this out is to check the numbers once the upcoming announcement hits, comparing decks like Infect and Bloom. Infect is certainly a deck with turn two kill potential, whereas it’s a little rarer in Amulet. But we also don’t have good numbers on those two decks yet, so we have to wait and see.

Never in this level of detail and never as a standalone piece. Given how frequently this comes up and how often it is misunderstood, I thought it was important to have one article that focuses exclusively on this critical topic. We’ve gotten a lot of positive feedback on this article, which suggests it was a good decision and one that is helpful to the Modern community.

I appreciate seeing empirical method/formal logic getting applied to mtg. It’s a shame that other writers have apparently not had any meaningful contact with philosophy or sociology because a huge chunk of the mtg community could really benefit from it.

Glad it’s been helpful! I totally agree that more writers and players need to use these methods in understanding the format. It would go a long way towards improving the community and how we process information.

Amulet bloom rarely breaks the turn 4 rule , most of the time even if you can get titan to hit turn 2 there is usually some answer to that play wether its a counterspell or a path to exile or even ghoast quarter can disrupt it . my point is this if the deck is so broken why isnt it completely dominating the format like other combo decks in the past (shoal infect , ur storm come to mind ) or even warping the format around it like treasure cruise and dig through time did ?
Its because even though the deck is good it is not the best deck in the meta right now, in my opinion the modern meta is very diverse and open to almost any deck being able to win ! I wish that people would take into consideration the overall state of the meta and prepare themselves for they’re individual events instead of them screaming about banning a deck they lost to!! I think that amulet is a deck that people just dont understand , and hopefully you guys here at modern nexus will make it a deck of the week so more mtg players can understand it !
Thnx for the article it was as always informative and provocative at the same time!

Did you read this article? Storm and infect were in the 5% range – and so is bloom. There was never a point where storm was making 20% of the meta – it was 5% and the consistency of turn 3 wins was around 25% which earned seething song a ban seat.

The whole point of the article was to create an actual definition that decks could be weighed against – best guess is 5% meta share and 25% pre-turn-4 win rate, and those are literally based on storm and infect bans. Bloom has the same prevalance at about 5% – the question is whether its winning pre turn-4 at the same 25%ish clip.

First of all, like I always say about Sheridan’s articles, what an amazing piece of work.
Secondly, I would just like to point out that, regarding Bloom, the average win turn is probably a little weak of an estimate for how quickly the deck “wins”. What I would find that could be a help this better, is a couple of things:
– Average turn 1st titan comes into play;
– Percentage of games Bloom wins, in games it has resolved a titan.

My theory is that a resolved titan gives such a huge advantage (pacts of all kinds + huge blocker/beater) that it has to be highly correlated with a game win. If that’s the case, then most games come down to “can u win before titan resolves”? And so, the average turn titan comes into play would be a, if not superior, very helpful in assessing the turn speed of this deck kill potential.

Although Stoddard discusses the concept, even he isn’t clear exactly how it applies to bans. Infect seems okay according to him, whereas old All In Red was not. But how does something like T1 Thoughtseize, T2 IoK, T3 Lily compare to that? Or Affinity’s hand-vomit starts? A turn 2-3 Titan? It’s impossible to know where to draw that line without being deeply subjective, and I’d rather stick with a more concrete measure until we knew more.

I’d IoK first before TS, normally they can’t cast the TS target next turn. Then Lili t3/4 this is a normal line of play for 8rack and look how successful my favorite deck is…
Oh, yeah. we don’t wanna talk about 8rack here, sorry I forgot…
😉

Also, I doubt anything is getting banned. Only things that I consider annoying/mandatory are Blood Moon, Snapcaster Mage and Spellskite.

Current metagame: 12/1 – 12/31

NOTE: Metagame % is calculated from the unweighted average of all MTGO leagues, paper T8s/T16s, and GP/PT/Open Day 2s in the date range. Data is tracked in the Top Decks page, which you can browse for more details.